hygrometer

hygrometer
    n 1: measuring instrument for measuring the relative humidity of
         the atmosphere
    

Hygrometer \Hy*grom"e*ter\, n. [Gr. ? wet, moist + -meter: cf.
   F. hygrom[`e]tre.] (Physics)
   An instrument for measuring the degree of moisture of the
   atmosphere.
   [1913 Webster]

   {Daniell's hygrometer}, a form of hygrometer consisting of a
      bent glass tube terminating in two bulbs, the one covered
      with muslin, the other of black glass, and containing
      ether and a thermometer. Ether being poured on the muslin,
      the black ball, cooled by the evaporation of the ether
      within, is soon covered with dew; at this moment, the
      inclosed thermometer gives the dew-point, and this,
      compared with the reading of one in the air, determines
      the humidity. Hygrometric
    

25 Moby Thesaurus words for "hygrometer":
      aerological instrument, aneroid barometer, aneroidograph,
      barograph, barometer, barometrograph, glass, hair hygrometer,
      humidor, hurricane-hunter aircraft, hygrodeik, hygrograph,
      hygroscope, hygrostat, hygrothermograph, psychrometer, radiosonde,
      recording barometer, sling psychrometer, vacuometer,
      weather balloon, weather instrument, weather satellite,
      weather vane, weatherglass